Temperature control in a ceramic membrane reactor

Abstract

A method for maintaining the temperature of an oxygen-selective ion transport membrane within a desired temperature range includes providing an ion transport reactor with the oxygen-selective ion transport membrane. An oxygen-donating feed gas is delivered to a cathode side at a first temperature, at a first rate, and at a first oxygen partial pressure and a reactant gas is supplied to an anode side at a second temperature and a second rate. A physical condition is then established within the ion transport reactor that favors the transport of elemental oxygen through the oxygen selective ion transport membrane as oxygen ions. One or more process variables are then regulated to maintain the temperature of the oxygen selective ion transport membrane within the desired range.

We claim: 
     
       1. A method for maintaining the temperature of an oxygen-selective transport membrane, contained within an ion transport reactor, within a desired temperature range which comprises: a) providing the ion transport reactor with said oxygen selective ion transport membrane that has a cathode side and an anode side;   b) delivering an oxygen-donating feed gas at a first temperature, at a first rate, and at a first oxygen partial pressure to said cathode side;   c) supplying a reactant gas to the anode side at a second temperature and at a second rate, said reactant gas being capable of reacting with oxygen;   d) establishing a physical condition within said ion transport reactor that favors transport of elemental oxygen through said ion transport membrane as oxygen ions;   e) transporting elemental oxygen obtained from said feed gas through said ion transport membrane as oxygen ions to provide transported elemental oxygen to said anode side; and   f) regulating one or more process variables to maintain said temperature of said ion transport membrane within said desired temperature range.   
     
     
       2. The method of claim 1 wherein regulating includes balancing exothermic heat generated by reaction on the anode side by inducing within the reactor at least one of: latent heat of vaporization of an injected liquid stream; an endothermic reaction; and a temperature rise in at least one fluid stream. 
     
     
       3. The method of claim 1 including determining the temperature of said oxygen selective ion transport membrane through direct measurement or through estimation based on at least one measured variable instead of direct measurement of the membrane temperature, and providing said determined temperature to a controller. 
     
     
       4. The method of claim 3 wherein said controller, responsive to said provided temperature, adjusts one or more of said feed gas temperature, said feed gas flow rate, said feed gas composition, said reactant gas temperature, said reactant gas flow rate and said reactant gas composition. 
     
     
       5. The method of claim 4 including the step of selecting said reactant gas to include at least one member of the group consisting of natural gas, methane, ethane, propane, butane, hydrogen, carbon monoxide, methanol and ethanol. 
     
     
       6. The method of claim 4 wherein said controller adjusts at least one of the temperature of said feed gas and the temperature of said reactant gas. 
     
     
       7. The method of claim 4 wherein said controller adjusts at least one of the flow rate at which said reactant gas is delivered to said anode side and the flow rate at which said feed gas is delivered to said cathode side. 
     
     
       8. The method of claim 4 wherein a cooling medium is delivered to said anode side to lower the reactant gas temperature at said anode side. 
     
     
       9. The method of claim 8 wherein said cooling medium is atomized water. 
     
     
       10. The method of claim 8 wherein said cooling medium is steam. 
     
     
       11. The method of claim 4 including the step of cooling said reactant gas prior to delivery to said cathode side. 
     
     
       12. The method of claim 11 wherein at least a portion of said reactant gas is bubbled through a water bath. 
     
     
       13. A method for maintaining the temperature of an oxygen-selective transport membrane, contained within an ion transport reactor, within a desired temperature range which comprises: a) providing the ion transport reactor with said oxygen selective ion transport membrane that has a cathode side and an anode side;   b) delivering an oxygen-donating feed gas at a first temperature, at a first rate, and at a first oxygen partial pressure to said cathode side;   c) supplying a reactant gas to the anode side at a second temperature and at a second rate, said reactant gas being capable of reacting with oxygen;   d) establishing a physical condition within said ion transport reactor that favors transport of elemental oxygen through said ion transport membrane as oxygen ions;   e) transporting elemental oxygen obtained from said feed gas through said ion transport membrane as oxygen ions to provide transported elemental oxygen to said anode side;   f) regulating one or more process variables to maintain said temperature of said ion transport membrane within said desired temperature range;   g) determining the temperature of said oxygen selective ion transport membrane through estimation based on at least one measured variable instead of direct measurement of the membrane temperature, and providing said determined temperature to a controller;   h) said controller, responsive to said provided temperature, adjusting one or more of said feed gas temperature, said feed gas flow rate, said feed gas composition, said reactant gas temperature, said reactant gas flow rate and said reactant gas composition; and   i) selecting said reactant gas to include at least one member of the group consisting of natural gas, methane, ethane, propane, butane, hydrogen, carbon monoxide, methanol and ethanol.   
     
     
       14. The method of claim 13 wherein said cooling medium is atomized water. 
     
     
       15. A method for maintaining the temperature of an oxygen-selective transport membrane, contained within an ion transport reactor, within a desired temperature range which comprises the steps of: a) providing the ion transport reactor with said oxygen selective ion transport membrane that has a cathode side and an anode side;   b) delivering an oxygen-donating feed gas at a first temperature, at a first rate, and at a first oxygen partial pressure to said cathode side;   c) supplying a reactant gas to the anode side at a second temperature and at a second rate, said reactant gas being capable of reacting with oxygen;   d) establishing a physical condition within said ion transport reactor that favors transport of elemental oxygen through said ion transport membrane as oxygen ions;   e) transporting elemental oxygen obtained from said feed gas through said ion transport membrane as oxygen ions to provide transported elemental oxygen to said anode side;   f) regulating one or more process variables to maintain said temperature of said ion transport membrane within said desired temperature range;   g) balancing exothermic heat generated by reaction on the anode side by inducing within the reactor at least one of: latent heat of vaporization of an injected liquid stream; an endothermic reaction; and a temperature rise in at least one fluid stream; and   h) determining the temperature of said oxygen selective ion transport membrane through direct measurement or through estimation based on at least one measured variable instead of direct measurement of the membrane temperature, and providing said determined temperature to a controller.